Blog Post

How biosensors could put a smartphone at the center of 21st-century medical care

A few years ago, University of Illinois engineer Brian Cunningham hosted an alumnus who’d made a fortune developing one of the earliest iPhone apps. “This person made a gazillion dollars on some trivial game,” he recalled with an incredulous laugh. “I thought, ‘there must be something better you can do with a smartphone.’”

Earlier in his career, after his parents died relatively young and within a few years of each other of lymphoma and prostate cancer, the electrical and computer engineering professor decided to shift his focus from biosensors for military applications like heat-sensing missiles to monitoring one’s health.

“Rather than bombing people, I decided to work on biosensors that could help diagnose disease,” he told me in a recent interview.

Brian Cunningham, University of IllinoisAnd his meeting with that wealthy game developer would prove to be another game changer. Cunningham gathered a group of students who agreed to volunteer their time for their senior design project developing a cradle and app for the iPhone 4 that would be capable of detecting a wide range of chemical and biological agents.

Their achievement made a big splash, but Cunningham said they’ve already gone well beyond it with additional work, and the future of smartphones that come equipped with built-in biosensors and dedicated cameras could be just a few years away.

To be clear, biosensors have been hot for years now. Sensors currently exist or are being tested for their ability to detect a wide range of targets, including:

gases like methane and sarin

explosives like TNT

chemicals like isopropyl alcohol

foodborne bugs like salmonella and listeria

allergens like peanuts

water contaminants like lead and pesticides

and infectious diseases like influenza and HIV

But it’s only in the past few years that more scientists have been developing ones that can or will be integrated into smartphones. Cunningham’s cradle, for instance, is in its worst light a clunky piece of extra hardware most people aren’t going to lug around every day. Integrating the sensor into the phone itself, and adding a second camera dedicated to biosensing instead of selfies, is the next step.

Based on the interest Cunningham is getting from phone developers and end users, he predicts this advancement is coming in just two or three years.

And then there’s the $10M Qualcomm Tricorder XPRIZE, which has 10 finalist teams from six countries working to build a “consumer-focused mobile device” that can not only capture five health metrics but also diagnose and interpret 15 different medical conditions. Teams are expected to showcase a range of next-gen biosensors behind their proposed devices when consumer testing begins in 2015. The winner is scheduled to be announced in early 2016.

Alex Hsieh, widely known for his work developing a fitness tracker for Atlas Wearables before being snatched up by Apple in June, isn’t so sure. The limiting factor when it comes to integrating all these sensors into gadgets, he said, is power consumption: “In the coming years more and more sensors will be added, whether to phones or watches, but I think the first issue that has to be addressed is power consumption. The more sensors you add on, the more battery draw.”

The wide range of biosensing applications could also act as a deterrent, he added, given people can be overwhelmed by too many choices. “It could take some time to get to a point where it’s useful data for the consumer,” he said. “And as soon as you overload, people start to not care, and that’s a line you should try not to cross.”

Overwhelming or not, the range of coming possibilities is certainly wide, and to people like Cunningham, tantalizing. A new mom could measure BPA levels in her breast milk or lead in her home’s water; a nurse could test for drug-resistant bacteria on the door knobs and light switches of a health clinic; a backpacker could check for contaminants in lake water; a teacher could confirm the absence or presence of peanuts in cafeteria food; a rancher could diagnose infectious disease on a cattle farm; an HIV positive patient could monitor viral load on a regular basis; the list goes on and on.

Here’s a quick snapshot of some of the latest biosensor research that is already adapted or being adapted to smartphones:

In Alex’s world, fitness is king. He acknowledged that his focus may bias him, but he sees the general consumer being most interested in measuring metrics like heart rate and sweat content for day-to-day health and fitness tracking. Testing for things like the flu or allergens have a time and a place, but when it comes to the general consumer, being able to detect things like explosives and gases is way too niche to justify spiking a phone’s battery consumption or overall cost.

How long it takes for biosensors to work their way into the vast majority of smartphones, and exactly what most of them will be used to detect, of course remains to be seen. But as the folks associated with Cell-all wrote: “The goal seems imminently achievable: Just as Bill Gates once envisioned a computer on every desk in every home, so [the Cell-all creator] envisions a chemical sensor in every cell phone in every pocket, purse, or belt holster.”